What kind of small mistakes would you let slide on a new workers first day?

Our new technicians tend to be super nervous their first day- new job, new environment, new people (all women at that!)

We have had trainees use alkaline cleaners where they should've used acidic.. or changed the thermostat up in a client's home without permission.. or parked in a driveway without knowing we aren't allowed-- all of these are learning lessons.

We are very lenient related to these things, but when it comes to disrespect toward other team members or our clients, we have pulled after 1-2 days.